On Saturday 24 February 2007 12:42 am, Matt Newell wrote: > On Friday 23 February 2007 14:34, Matt Newell wrote: > > On Friday 23 February 2007 12:52, Matt Newell wrote: > > > On Friday 23 February 2007 12:38, Michael Guntsche wrote: > > > > On Feb 23, 2007, at 20:43, Matt Newell wrote: > > > > > > ... > > > > > > > Hello Matt, > > > > > > > > Can you try and change the connect to a QueuedConnection? It looks > > > > like it is using a "DirectConnection" now. > > > > I was sure I tried that before, but back then I was using events and > > > > not signals. > > > > > > It's already (correctly) using a queued connection to send the signal. > > > I've already tracked it down further and eliminated one of the deadlock > > > code paths by putting a /ReleaseGIL/ annotation on QLabel::setText. > > > There is another deadlock though happening in the connect call which > > > i'm tracking down now. > > > > > > > I tried it on my computer, but although the "connect" returns True I > > > > do not get the emitted signal in my main thread. > > > > I do not understand why. > > > > > > Hmm, i'm not sure why that would happen. > > > > So here's the deal. In order to avoid deadlocks we must avoid running > > any Qt code that will require a lock while the GIL is locked. This is > > because we can't avoid the opposite, which is acquiring the GIL while Qt > > is holding a lock( For example Qt holds a lock while copying signal data > > for queued connections, and we have to run python code for that. ) To > > avoid a deadlock we must avoid one or the other. > > > > This means that any Qt calls that do a connect, or create/destroy any > > qobjects must first release the GIL. There may be other code paths in Qt > > that require the same care. > > > > Try testing with this patch, it eliminates all deadlocks for me. > > I still get deadlocks when destroying the threads unless I add /ReleaseGIL/ > to the QThread dtor. > > I think that right now there are many potential deadlocks in PyQt. All > QObject and derived classes need their ctors and dtors marked /ReleaseGIL/. > All connect/disconnect functions, any functions that indirectly delete or > create qobjects, etc. Essentially the entire api needs to be reviewed.
In the meantime you could try changing PyQt's configure.py (in set_sip_flags()) so that it invokes sip with the -g flag. Phil _______________________________________________ PyKDE mailing list PyKDE@mats.imk.fraunhofer.de http://mats.imk.fraunhofer.de/mailman/listinfo/pykde
